The evergreen forests are normally found in areas which get more than 250 cms. of annual rainfall.

The variation in duration of sunlight at different places is due to differences in latitude, altitude, season and duration of the day.

The character and extent of vegetation are mainly determined by temperature along with humidity in the air, precipitation and soil. 

Since the inception of Central Zoo Authority in 1992, the Authority has evaluated 347 zoos, out of which 164 have been recognized.

Hence, 164 is the correct answer.

A tropical rainforest occurs roughly within the latitude 28 degrees north or south of the equator (in the equatorial zone between the Tropic of Cancer and Tropic of Capricorn). These forests experiences high average temperatures and a significant amount of rainfall.

Mahogany is not essentially a species of the Himalaya vegetation. Mahogany is a species of tree found throughout the Caribbean, central and South America not in Himalayas.

The name Sundarbans is thought to be derived from sundri or sundari (Heritiera fomes), the name of the large mangrove trees that are most plentiful in the area. The forestland transitions into a low-lying mangrove swamp approaching the coast, which itself consists of sand dunes and mud flats. Mangrove forests constitute about two-fifths of the Sundarbans region’s overall surface area, with water covering roughly half of that area. The landscape is constantly being transformed by the erosional forces of the sea and wind along the coast and by the enormous loads of silt and other sediments that are deposited along the myriad estuaries. Human activity has also altered the landscape, notably through forest removal, which accelerates erosion. In addition, because considerable amounts of river water have been diverted upstream for irrigation and other uses, salinity in the mangrove swamps has moved farther inland, especially in the Indian sector of the territory.

Newspapers are made from a type of paper called newsprint. Coniferous softwoods such as spruce, pine, and cedar provide long (average 3mm), strong fibers. Newsprint needs strength enough to withstand the demands of fast printing presses, the ability to accept high-quality color printing and enough opacity to prevent the printing showing through the pages. In most temperate coniferous forests, evergreen conifers predominate, while some are a mix of conifers and broad leaf evergreen trees and/or broad leaf deciduous trees.

Hence, option C is the correct answer.

Perennial, evergreen and woody plants are Cycas, Pinus(gymnosperms).

The virgin vegetation, which  are purely Indian are known as endemic or indigenous species but those which have come from outside India are termed as exotic plants.

Cultivated crops and fruits, orchards form part  of vegetation but not natural vegetation.

Natural vegetation refers to a plant community, which has grown naturally without human aid and has been left undisturbed by humans for a long time

The undulating and rough terrains are areas where grassland and woodlands develop and give shelter to a variety of wildlife.

The species of animals are referred to as fauna. 

The term flora is used to denote plants of a particular region or period.

The feature of the Tropical Evergreen Forests are: 

1. The trees reach great heights up to 60 metres or even above. 
2. There is no definite time for trees to shed their leaves.
   
3. Since the region is warm and wet throughout the year, it has a luxuriant vegetation of all kinds trees, shrubs and creepers giving it a multilayered structure
   

4. They are at their best in areas having more than 200 cm of rainfall with a short dry season.
   

Tropical Evergreen Forests are restricted to heavy rainfall areas of the Western Ghats and the island groups of Lakshadweep, Andaman and Nicobar, upper parts of Assam and Tamil Nadu coast.

In India, almost the entire rainfall is brought in by the advancing southwest monsoon (June to September) and retreating northeast monsoons. Areas of heavy rainfall have more dense vegetation as compared to areas of less rainfall.

In regions with less than 70 cm of rainfall, the natural vegetation consists of thorny trees and bushes. 

Tropical Evergreen Forests are at their best in areas having  more than 200 cm of rainfall with a short dry season.

On the slopes of the Himalayas and the hills of the Peninsula above the height of 915 metres, the fall in the temperature affects the types of vegetation and its growth, and changes it from tropical to subtropical temperate and alpine vegetation.

The dry deciduous forests are found in areas having rainfall between 100 cm and 70 cm.

The region where the Tropical Evergreen Forests are found is warm  and wet throughout the year, it has a luxuriant vegetation of all kinds trees, shrubs and creepers giving it a multilayered structure. 

Some of the commercially important trees of this Tropical Evergreen are ebony, mahogany, rosewood, rubber and cinchona. 

Sarpagandha is used to treat blood pressure.  It is found only in India.