Which of the following statements reflect the strengths of EBITDA?

a$.$ EBITDA is widely used to assess a business's fundamental profitability, and as a "pure" measurement of core cash flow made available.

b$.$ Earnings are assessed before these other variable accounting activities are incurred, as any non$-$operational decisions are removed.

c$.$ EBITDA can only be used if there is depreciation and amortization.

d$.$ Both a$.$ and b$.$

e$.$ None of the above.