Solution:Here, for winning either P or Q has to pick a white card Q can get a chance to pick card if and only if P picks a black card i.e. P loses.Hence, option (b) and (c) get eliminated. Also, P and Q both can not lose the game as card picking will be continued till any of both pick a white card to win the game and there are limited number of cards. Hence, option (d) also get eliminated.
Now, check option (a), we find it correct as P pick a black card and Q picks a white card.