As passed by the Congress after McKinley delivered his war message to Congress, the declaration of war against Spain was modified by the Teller Amendment, which stipulated that

Athe United States wouldn't annex Cuba.
Bthe United States reserved the right to annex Cuba.
Ctrade with Spain would continue as usual.
DSpain must abandon all claims to territories in the Western Hemisphere.

Verified Answer :

The answer is letter A.
It was an revision made to a joint resolution that was passed on April
20, 1898 regarding President William McKinley’s declaration of war to Spain, It
stated that the United States must never annex Cuba and all the Cubans to
govern the Island.