Answer: b. Change invoke to invocation.
Step-by-step explanation: in the given sentence " If we do not accelerate, we will be late for the invoke ceremony at the chapel for the new teachers", we can see that there is an incorrect usage by saying "the invoke ceremony", in this case, the word "invoke" is a verb that expresses the action of calling upon a person for help or guidance, the use of a verb in this case is incorrect, we must use a noun instead, so the correct expression would be: "the invocation ceremony".