In each of the questions below, a sentence is given with two blanks. Choose the option that best fills both blanks to make the sentence grammatically and contextually correct. The tribunal’s ruling that the bilateral investment treaty’s ______________ clause had been invoked in bad faith effectively ______________ the multinational’s attempt to shield its speculative derivatives portfolio from the host government’s newly enacted windfall taxation regime.

The sentence describes a legal ruling about a specific clause in a bilateral investment treaty (BIT) that a multinational company had invoked. The clause was found to have been invoked “in bad faith” — meaning it was being used improperly. The ruling then did something to the multinational’s attempt to shield its derivatives portfolio from a windfall tax — requiring a verb meaning to defeat or render ineffective that attempt. Umbrella clause is a specific, established term in international investment law — it is a BIT provision that “covers” or protects all investment commitments made by the host state, and it is precisely the type of broadly worded clause that multinationals invoke to shield diverse asset classes (including derivatives portfolios) from regulatory interventions. Its invocation “in bad faith” for speculative financial instruments is a documented phenomenon in investment treaty arbitration.  Neutralised means rendered ineffective — precisely describing the consequence of the tribunal’s ruling on the company’s legal strategy. Hence (d) is the correct answer.