The (i)___________manner by which the poet conducted his personal life lay in sharp contrast to his public persona: on a brightly lit stage, in front of an appreciative crowd, he displayed (ii)___________that cheered even the gloomiest souls.

The above highlighted are the clues to solve the question. As the poet cheered the gloomiest souls he displayed something positive like a funny nature. As for the first blank we need something opposite with respect to the first blank, gloomy can work.

Thus, only Morose & Jocundity works.

Here, I knew what Jocular meant, so it was easy for me to identify what Jocundity could mean. If you do not know what Jocundity means, we can negate the other options according to the requirement and the arrive at Jocundity.

IMO B & F

Hope this helps!