Which of the following sentences uses the active voice?

a

Several ingredients were used by the chef to make the stew.
b

The chef used several ingredients to make the stew.
c

To make the stew, several ingredients were used.
d

The stew was made by the chef using several ingredients.

b

The chef used several ingredients to make the stew.

The sentence that uses the active voice is:

b

"The chef used several ingredients to make the stew."