Which letter-cluster will replace the question mark (?) to complete the given series?
MRFL, RYKS, ?, BMUG, GTZN
1
TFQY
2
TDOX
3
WFPZ
4
SEPY
Which letter-cluster will replace the question mark (?) to complete the given series?
MRFL, RYKS, ?, BMUG, GTZN