question: What helps to harden an egg shell?
choices.text: less friction prevents water loss decreased calcium carbonate calcium carbonate outer membrane poor diet Stomata closing maintain a thin egg shell
choices.label: A B C D E F G H
formatted_question: What helps to harden an egg shell? (A) less friction (B) prevents water loss (C) decreased calcium carbonate (D) calcium carbonate (E) outer membrane (F) poor diet (G) Stomata closing (H) maintain a thin egg shell