What is the authenticity of the phrase (وَكَوَاعِبَ أَتْرَابًا - and buxom companions of equal age)?

It is more befitting for a Muslim to turn away from the doubts raised by disbelievers, especially if he is unable to refute them, for the heart is weak and doubts are snatching. As for the verse "full-breasted [companions] of equal age," there is no flaw in it. "Kawa'ib" refers to young women who have reached the age of fifteen, and "tak'ab thudayyuhunna" means their breasts have become rounded and prominent. "Atrāb" means of equal age. The verse describes the women of Paradise by their beauty, young age, and being of equal age, and this aligns with the inclinations of sound human nature.