An informal and unstructured communication channel that cuts across formal channels of communication is called:

My answer is same as other experts, which is option (D)

>>>>>>>>>>>>  d. the grapevine. >>>>>>>>>>>>>>>>

Agree with professionals..... 

answer D ___________________________________

Answer ___________________ d)

 d. >>>>>>>>>>>>>>>>> the grapevine.

Option -----------------------D

Thanks

The answer is :Option ( D )