In certain ecosystems where light is not available, a process converts chemical energy into high-energy carbohydrates. What is this process called? A. photosynthesis
B. dark reactions
C. chemosynthesis
D. chemical bonding

The process in which autotrophs capture light energy and use it to convert carbon dioxide and water into oxygen and sugars is called photosynthesis. The process in which autotrophs use chemical energy to produce carbohydrates is called chemosynthesis.

Explanation:

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.