When adding a vowel suffix to a word, which of the following is the only case where the suffix can be added without making another change?
A. The word ends with a consonant preceded by only one vowel (ship + ing).
B. The word ends in y (cry + ed).
C. The word ends with a silent e (defense + ive).
D. The word ends with a consonant preceded by two vowels (cheat + er).