The rate of photosynthesis would be maximum at the equator because the the rate of photosynthesis depends on the light intensity. Maximum intensity of light occurs at the equator, and gradually decreases with increasing distance from the equator to the south and north poles. So the correct answer is 'Equator'.
Biodiversity day or the Biological diversity day is a UN sanctioned day celebrated internationally. It addresses the promotion of biodiversity issues. Currently, the day is held on May 22. Earlier, it was held on December 29 to celebrate the day in which the Convention on Biological Diversity came into action.