Pensions Rate of Return

So some questions state a total return but others state acturial rate and others state duration matching (mature plan). My question is does the actuarial rate consider inflation? Also total return would only be important if your liabilities are inflation linked. Do we just assume that all DB pension plans are inflation linked? what’s the correct answer if you are looking at a relatively young plan?

Cheers

Actuarial rate is used to discount liabilities their present value so ive got to assume it includes inflation, no?