Is the underlined verb in the sentence a linking verb or a verb?

my brother has eaten all the chili in the pot.

a.
linking verb

b.
verb

How can you avoid the problem of groupthink? a. by choosing a group leader to direct the group b. by composing the team of only like-minded individuals c. by encouraging all members to voice their opinions d. by keeping quiet when you disagree with another group member's opinion