In the following question, a series is given with one or

In the following question, a series is given with one or more number(s)/alphabet missing. Choose the correct alternative from the given options.
PQR_, PQ_S, P_RS, _QRS

The given letter series in below pattern.
P Q R S
After completing the pattern, we will get complete letter series.
P Q R S/ P Q R S/ P Q RS/ P QRS