f we use extended Vigenere cipher $(26$ English letters and $10$ decimal digits$)$ to encrypt $$ENG$1234$ using key word $$ITCS$43.$ Then, we obtain $----------------------$ as a ciphertext. Note that Z$=25,0=26,1=27,2=28......$ Hint: Use modular arithmetic.

a$.$

M$6$IJXXC

b$.$

None of these

c$.$

M$6$IJWWC

d$.$

M$6$IJWXC

e$.$

M$6$IJXWC