How to calculate the training set error (last question!)

Could you please do this step by step, with the calculations? As I don't understand HOW to get to the answer...

Decision Trees You're taking a date to the movies. To be sure that you both enjoy the night out, you choose to select a movie using a decision tree that you develop on data about movies you both watched. Table 1 contains the training data. Oscar nominee Lead Liked by both? enre Male Romantic Comedy Yes No Male Horror Yes No Male Romantic Comedy No No Male Arthouse No No Arthouse Yes Male No Romantic Comedy No Female Yes Yes Horror No Male Horror Yes Female Yes Table 1: Movies 3. The ID3 algorithm would select Lead as the root node of the tree. What will the algorithm split on next when Lead Male? A: Genre B: Oscar nominee C: No further split, predict Yes D: No further split, predict 'No' 4. What will the algorithm decide for the Lead Female branch? A: Genre B: Oscar nominee C: No further split, predict "Yes" D: No further split, predict 'No' 5. Suppose that the decision tree is not elaborated further, i e., there is no further split after the one you identified in question 3. Calculate the training set error for the resulting tree. A: 0% B: 12.5% C: 25% D: 37.5% Decision Trees You're taking a date to the movies. To be sure that you both enjoy the night out, you choose to select a movie using a decision tree that you develop on data about movies you both watched. Table 1 contains the training data. Oscar nominee Lead Liked by both? enre Male Romantic Comedy Yes No Male Horror Yes No Male Romantic Comedy No No Male Arthouse No No Arthouse Yes Male No Romantic Comedy No Female Yes Yes Horror No Male Horror Yes Female Yes Table 1: Movies 3. The ID3 algorithm would select Lead as the root node of the tree. What will the algorithm split on next when Lead Male? A: Genre B: Oscar nominee C: No further split, predict Yes D: No further split, predict 'No' 4. What will the algorithm decide for the Lead Female branch? A: Genre B: Oscar nominee C: No further split, predict "Yes" D: No further split, predict 'No' 5. Suppose that the decision tree is not elaborated further, i e., there is no further split after the one you identified in question 3. Calculate the training set error for the resulting tree. A: 0% B: 12.5% C: 25% D: 37.5%