Doubt in a quiz question

in this question
If t=(‘Tanya’, ‘ate’ , ‘3’, ‘apples’)
Which of the following is incorrect?
a)print(t[2])
b)t[2]= 4
c)print(len(t))
d)print(t[0])

why B is the answer?
won’t it change the number 3 into 4?
if no, how will it be changed?