Probability of exactly 1 head in 2 coin flips = ?

Two coin flips produce four equally likely ordered outcomes: HH, HT, TH, and TT. Exactly one head occurs in two of these outcomes: HT and TH. Therefore, the probability is 2 favorable outcomes out of 4 total outcomes, or 2/4 = 1/2. This can also be computed using the binomial model. There are n = 2 independent trials, success probability p = 1/2, and exactly one success is required. The binomial calculation is C(2,1)(1/2)^1(1/2)^1 = 2 × 1/4 = 1/2. Option B, 1/4, counts only one of the two favorable sequences. Option C, 3/4, includes outcomes with at least one head rather than exactly one head. Option D would mean certainty, which is impossible because HH and TT do not satisfy the condition. Study Guide references/topics: sample spaces, coin-flip probability, binomial probability, independent events.