Verbal - "Insert A Letter"

Example

tea [?] akes
fro [?] op

On the answer sheet you are given five letters to choose from. Ak Bc Cl Dm Eg
Fit each letter in turn into the brackets to see if you can make four words. You may find that some letters will make up one, two or three words but not all four. It is important to check that you have made four words. In the question example: tea(k) is a word, but (k)akes is not a word tea(c) is not a word tea(l) is a word, (l)akes is a word, fro(l) is not a word tea(m) is a word, (m)akes is a word, fro(m) is a word, (m)op is a word. So the answer must be (m)