What is the mood of tell tale heart with text evidence

What effect does this excerpt have? the line of the horizon was clear and hard against the sky, and in one particular quarter it showed black against a silvery climbing [glow] that grew and grew. at last, over the rim of the waiting earth, the moon lifted with slow majesty till it swung clear of the horizon and rode off, free of *moorings; and once more they began to see surfaces—meadows wide-spread, and quiet gardens, and the river itself from bank to bank, all softly disclosed, all washed clean of mystery and terror, all radiant again as by day, but with a difference that was tremendous. their old haunts greeted them again in other *raiment, as if they had slipped away and put on this pure new apparel and come quietly back, smiling as they shyly waited to see if they would be recognized again under it. fastening their boat to a willow, the friends landed in this silent, silver kingdom, and patiently explored . . then a change began slowly to declare itself. the horizon became clearer, field and tree came more into sight, and somehow with a different look; the mystery began to drop away from them. a bird piped suddenly, and was still; and a light breeze sprang up . . rat . . sat up suddenly and listened with a passionate intentness. mole, who with gentle strokes was just keeping the boat moving while he scanned the banks with care, looked at him with curiosity.

What sentence correctly uses it’s underlined relative pronoun?

Will give read the sentence: (blank) starting to rain outside. which is the best word to complete the sentence? a : its b : its’ c : ’tis d : it’s