Read the following article and answer the question by choosing from the options.

Ahh ... on weekends we need to input a PIN code on top of scanning . Well , let 's input the PIN ... Normally when I do this , I can hear the doors unlocking immediately . This time there was no response .

Why do they need to input a PIN code ?
Choices:
A). They need to input the code because it 's the weekend .;
B). None of the above choices .;
C). They need to input the code because it 's Wednesday .;
D). They need to input the code because it 's Tuesday .;...A:
A).