The correct answer is (a) \(\frac{1}{2}\)
The best I can explain: Deck of cards contains 52 cards. There are 13 cards of hearts, spades, clubs and diamonds. The 13 cards are A, 2, 3, 4, 5, 6, 7, 8, 9, 10, J, Q, K. Heart and diamond cards are red cards and clubs and spades are black card. Hence, we have 26 red cards and 26 black cards in a deck. The probability of picking a red card is \(\frac{1}{2}\).