On November $16,$ a small company starts transitioning to a new accounting package during their holiday break. Suddenly, on April $1,$ when employees return to work at $9$:$00$ a$.$m$.,$ all computers in the accounting department found that the files have been encrypted, a message appears telling the victim what has occurred and that a fee must be paid to receive a key to unlock them. What type of ransomware attack is likely to have infected the computers?

a$.$ blocking ransomware

b$.$ kidnapping ransomware

c$.$ locking ransomware

d$.$ eavesdrop ransomware