How to reduce application size without removing the -ObjC flag using Cocoapods

Question

I have 1 iOS application, 3 libraries are required for this application

Library A has libA.a, Objective-c class files in library A, requires the libA.a file.
There are several images in library B, the Objective-c class files in library B require these images.
The C library does not have any ".a" or any images, just Objective-c class files and a lot of junk files

If I remove the “-ObjC” flag in my application, libraries A and B will not work.
If I keep the "-ObjC" flag, everything is fine, but the application size is huge.
Since this flag will contain all the objects included in the C batch library in the final binary.

So my question is how to set the “-ObjC” flag in a special library (here A and B, not C) when working with Cocoapods to reduce the final size of the application.

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