Which develop the theme in the rainy day?

1. noticing the new green grass sprouting
2. talking to someone about his problems
3. remembering the sun behind the cloud
4. making a new friend

plz ! asap

The correct option is 3.
The theme of a story or poem refers to the underlying message which the author is trying to convey. In the poem,  'The rainy day', the author was talking about the present dark moment of his life  and he was comparing his experience with the darkness that accompany rainy, dark and dreary days. But he reminded himself that those dark days are occasional events which no man can avoid and he believes that the sun will shine again. 
The underlying message of this poem is that no condition is permanent, even though things may not be as one wants them today, things will surely get better tomorrow, it will not be dark forever.