Which element is most likely to bend without breaking?

Among the elements listed—carbon (C), iodine (I), silicon (Si), and cobalt (Co)—silicon (Si) is the most likely to exhibit the property of bending without breaking, particularly in its various forms such as silicon wafers. Silicon is a metalloid with some metallic properties and can be processed into materials that are both flexible and durable.

Carbon, in the form of graphite, is also flexible, but if considered in its diamond form, it is very brittle. Iodine is molecular and not typically associated with any substantial structural integrity. Cobalt, being a metal, can also bend somewhat but might not have the flexibility of silicon structures.

Thus, the answer is silicon (Si).