Mandarin Test: Difference Between “们(men)” and “大家(dàjiā)”

Please choose the correct answer to fill in the blank.
Jack appeared in a party and said hello to everyone.
Jack：Péngyou___,dàjiā___hǎo！
Jack：朋    友 ___，大家___好！
Jack:  Hi there, everyone!
Blare：Nǐhǎo，Jack！
Blare：你好，Jack！
Blare:  Hi, Jack!
A. 们(men),  /
B.  /,  们(men)
C.  /,  /
D. 们(men)，们(men)