Read each sentence carefully and select the option with the sentence written correctly. yo necesitas un pantalón. tú te gustas un pantalón. yo me gusta un pantalón. usted necesita un pantalón.

Usted necesita un pantalón.

Explanation:

For the first one it should be yo necesito because it is talking about yourself.

For the second one it just doesn't make sense.

the third one you wouldn't use "Yo" in front of Me gusta.

As you can see only the last option is correct.

Hope this helps!

Have an awesome day!