Dayshawn can choose two of his four t-shirts to take on a weekend trip. if the t-shirts are labeled a, b, c, and d, which choice represents the sample space, s, for the event? s = {abcd} s = {abcd, dcba} s = {ab, ac, ad, bc, bd, cd} s = {ab, ba, ac, ca, ad, da, bc, cb, bd, db, cd, dc}