Question 511351
You can list them:
T EELR T
T EERL T
T REEL T
T LEER T
T RLEE T
T LREE T
T EREL T
T ELER T
T LERE T
T RELE T
T ERLE T
T ELRE T
I think that's all. It looks like (e) 12 is the answer