Answers:
1) No vengan tarde a mi fiesta - D) los amigos.
Do not come late to my party - to the friends.
2) No lleves mucha ropa - C) tu mejor amigo.
Do not take a lot of clothes - your best friend.
3) No salgamos solos - B) a los pasajeros en un tour contigo.
Let's not go out on our own - to the passengers on a tour with you.
4) No lleve una cámara grande - A) usted.
Do not carry a big camera - you (formal).
Step-by-step explanation:
The task given was to match each command to its respective subject. The mood used in these sentences is the IMPERATIVE. The imperative mood is useful to give commands and orders to others.
In Spanish, verbs must always agree in number with the nouns. That's why "salgamos" and "vengan" (plural verbs) are matched with the plural subjects: "your friends" and "the passengers"; while "lleve" and "lleves" (singular verbs) are matched with the singular subjects: "your best friend" and "you".