The correct answer is A. timid.
Timid means shy or nervous. It is the opposite of bold or courageous.
Obedient means willing to do what someone tells you to do. It is the opposite of disobedient or rebellious.
Forgiving means willing to let someone off the hook for something they have done wrong. It is the opposite of unforgiving or resentful.
Forgetful means having a poor memory. It is the opposite of having a good memory or being forgetful.
In the sentence “His vindictive nature often came up for comment among his friends,” the word “vindictive” means “having or showing a desire for revenge.” This means that the person in question is likely to hold grudges and seek to get back at
people who have wronged them. This is the opposite of being timid, which means being shy or nervous.The other options are not as relevant to the sentence. Obedient means willing to do what someone tells you to do, but this does not have anything to do with vindictiveness. Forgiving means willing to let someone off the hook for something they have done wrong, but this is also not relevant to vindictiveness. Forgetful means having a poor memory, but this is also not relevant to vindictiveness.