Select the option that demonstrates proper subject-verb agreement.
a. Peter's running shoes needs to be replaced. He and his friends run every day. Therefore, his shoes wear out quickly.
b. Peter's running shoes need to be replaced. He and his friends run every day. Therefore, his shoes wear out quickly.
c. Peter's running shoes needs to be replaced. He and his friends runs every day. Therefore, his shoes wears out quickly.
d. Peter's running shoes need to be replaced. He and his friends run every day. Therefore, his shoes wears out quickly.