Select the letter-cluster that can replace the question mark (?) in the following series.
qDx, nHs, kLn, hPi, ?1
EtD
2
eSd
3
eTd
4
fTe
5
None
Select the letter-cluster that can replace the question mark (?) in the following series.
qDx, nHs, kLn, hPi, ?