Answer:
C. demand of rainforest timber and exotic animal's
Step-by-step explanation:
Biodiversity refers to the combination of biological and diversity. In this, it shows the varieties of life than could be found on earth in terms of plants, animals, etc
For not reducing the biodiversity on earth, Jacob should be researched on rainforest timber demand and the exotic demand so that the biodiversity could not decline
Therefore the option c is correct
Hence, all the other options are wrong.