Read the following statements :

a) Water stress causes stomata to close and reduce availability of CO₂ in leaf.

b) The temperature optimum for photosynthesis of different plants does not depend on habitat they are adapted to.

c) Light reactions are also temperature sensitive but they are affected to a much lesser extent.

d) Current availability of CO₂ levels is limiting to the plants C_3.

e) CO₂ is major limiting factor for photosynthesis.

f) Except for plants in shade or in dense forests light is rarely a limiting factor.

How many statements are correct?