Difference between apologies and apologize

[deleted]

Test No. incompl/inter-64 "How to apologize", question 3

Please send my ......... to the meeting as I shan't be able to attend.

(a) apologies
(b) apologize
(c) apologized
(d) apologizing

Test No. incompl/inter-64 "How to apologize", answer 3

Please send my apologies to the meeting as I shan't be able to attend.

Correct answer: (a) apologies

Your answer was: incorrect
Please send my apologize to the meeting as I shan't be able to attend.
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what the different between apologize and apologies ?

[Torsten]

Apologies is a noun and apologize is a verb.

Please, take my apologies.
I want to apologize.

TOEFL listening lectures: A lecture from a life sciences class

[Luby]

Good Evening!
What is the meaning of shan't?Its my first time to encounter this word.