Question

The function of a specific enzyme is most directly

Answer 1

The answer is 2. 

Enzymes work to speed up chemical reactions by changing what goes into the reactions (substrates) into different molecules. To do so, these enzymes bind with the substrates, making the physical form very important. The lock and key method explains that enzymes and their corresponding substrates are shaped very specifically to be able to fit into one another to undergo this change.