(A) Converging lens
When the eyeball becomes too small, light focuses behind the retina (hypermetropia). A converging (convex) lens corrects this by converging rays to form the image on the retina.
Source: The Human Eye and the Colourful World, Section 10.2(b)
A reduced eyeball size causes hypermetropia (far-sightedness). The correction requires a convex/converging lens, not diverging. Bifocal is for presbyopia; cylindrical is for astigmatism. Examiners expect you to link "reduced eyeball → hypermetropia → converging lens."