Read each sentence to find out whether there is any grammatical error in it. The error, if any, will be in one part of the sentence. Choose the option corresponding to that part. If the sentence is correct, mark "No error".  (a) Despite the board of directors having  (b) unanimously approved the ambitious merger,  (c) the CEO, alongside several key stakeholders, are  (d) hesitant to proceed without conducting a rigorous financial audit.  (e) No error.