Please help me with the following questions. Thank you!

In the proof by induction of the theorem vn e N. n e 1 -* 2 + 4 + + 2n = n2 + n, which of the following would be the proper way' to state the base case? 0 When n = D, the sum consists of the first term 0 and the formula shows 0' + 0 = 0 0 When n = 2. the sum consists of the first term 2 and the formula shows 11 + 1 = 2 C) When n = 1. the sum consists of the first term 1 and the formula shows 11 = 1 Q When n = 1, the sum consists of the first term 2 and the formula shows 12 + 1 = 2 Which of the following rational number examples provides a disproof of the universal statement "en E e l}, 1ft] 5 q"