问题 单项选择题

If p and q are statements, which of the following formulas is tautological ( )

A.┐ (p→∧q

B.(p∨→p∧q

C.(q∧(p→)→p

D.((p→∧→q

答案

参考答案:D

多项选择题 案例分析题
单项选择题