To illustrate the point rightly made by Babbabooey:
Imagine a company with Assets = 100, Equity = 60 and Liabilities (debt) = 40. If the company were to lease an additional asset worth 10 under an operating lease agreement, neither the asset itself nor a liability would be recognised and the debt to assets ratio would stand at:
Debt/Assets = 40/100 = 0.4
If the same asset (worth 10) were leased under a finance lease agreement, the balance sheet effect would be to increase assets and liabilities by 10 resulting in: Assets = 110, Equity = 60 (no change) and Debt = 50. The adjusted debt to assets ratio would be:
Debt/Assets = 50/110 = 0.45,
… so it has gone up. In fact, the only time that it would not, would be the case of asset being 100% debt financed, i.e. no equity.
If you are not sure of the ratio impact of any transaction or event in the exam, I strongly recommend that you attempt to run a mini simulation like the one above. It will always work, whatever the numbers chosen.