CFAI online test - Allison - Treasury bonds futures

For question 4, selling the S&P 500 index futures makes sense as the index price decrease. But when the Treasury bond yields will have declined in 3 months, what would be the strategy then? Wouldn’t be sell US treasury bond futures since that’s not the answer, but buying Treasury bond futures doesn’t make sense either.

With respect to Client D’s market view, Allison will most likely:

buy S&P 500 Index Futures and buy U.S. Treasury bond futures sell U.S. Treasury bond futures sell S&P 500 Index Futures

I believe a decline in yields means bond prices will go up and you want to buy bond futures not sell.