When we fail to reject the null hypothesis, we:

i need help on this question it provide me with four answers that i could choose, but only one can be the correct one, please help me.

These are the options to answer this question i have :
A)have committed a Type II error
B)claim that a significant difference exists between groups
C)conclude that error is responsible for our difference.
D)have a tobtained value greater than our tcritical value