How to calculate the 8 days leaves in same month?

How to calculate 8 days taken leave in same month. One of our employee now having the leave balance - CL 7, SL 3.5, PL 4., In this case how to consider the 8 days leave taken in same month.
Ex- The taken 8 days leave consider as per below., which on is correct or tell me the correct calculation
Option 1 - leave consider as CL 7 + PL 1 days
Option 2 - leave consider as CL 4+ PL 4 days
Option 3 - Leave consider as CL 2 + PL 4 + LOP 2 days.

In general, CL is not allowed to be combined with any other leave and SL is availed only for medical reasons. Importantly, any intervening holiday is not counted in CL. There would be at least a weekly off day in 8 days in continuity so at the max. there could be only 7 working days and the CL balance would suffice. There is also a concept of advance credit of leave, that means looking to the genuine need, leave is allowed to be availed in advance. So allow the employee advance of PL on his request and adjust the advance credit against future entitlement.
Looking to the situation, it appears it is high time to formulate a clear leave policy and administer it properly.

I do agree with the observation of Mr.KK!HR in view of his own service experience in prominent P.S.U. The type of advance leave he's mentioned is called as " Leave-not due". It is virtually the annual leave with wages or earned leave to be earned by the employee in future but granted in advance. Another aspect of leave sanction though which itself being a matter of discretion subject to exigencies of work, is that the employer should sanction the particular type of leave applied for only and not according to his own discretion. The exercise of discretion would arise only when there is shortage of credit in the particular type of leave applied for.

In your particular case the 04 PL can be exhausted and advance/ leave not due as suggested by KK!HR and Mr.Umakanthan, as per his eligibility/discretion of Management. Or if the Management is not willing to give him credit make LOP for 04 days by duly informing him.

I would suggest 7 days C/L and 1 day w/o pay if so urgent.
Or leave be restricted to 7 days only.
CL and PL cannot be combined.