(My sentences)
a. Tom is grateful that he is (now) admitted to the school.
b. Tom is grateful that he has been admitted to the school.
c. Tom is grateful that he was admitted to the school.
d. Tom is grateful to be admitted to the school.
(The context: Tom has just got an e-mail with permission from the school.)
Which ones do you think are correct and natural? I am not sure about (a).

Student or Learner