We are not told whether Mrs. D shook hands with each of her guests. She may have shaken hands only with the males, only with the females, all of them, or any other number. From the way the question is worded, she could have shaken hands with Mr. B and Mrs. C and no one else.
Also, we cannot tell if all of the guests shook hands with Mrs. D and not with one another. For example, if Mrs. D shook everyone's hand, but Mr. and Mrs. A shook hands only with Mr. C, then the results are off.
Boru
Also, we cannot tell if all of the guests shook hands with Mrs. D and not with one another. For example, if Mrs. D shook everyone's hand, but Mr. and Mrs. A shook hands only with Mr. C, then the results are off.
Boru
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