What is the opposite of serious

It is letter b
los empleados se quejan de no tener un buen sueldo.

Let me see the picture 

Anybody planning on traveling to a spanish-speaking nation sometime in the next months or so have to make a program so that can make a dissent conversation in spanish or just to understand when folks talk to them due to the fact by the time your trip rolls around you must be conversationally fluent or rather near to it with the assist. hope this

Dato i think not100% sure