Final answer:
The process to dissolve a tenants in common ownership when owners cannot agree is known as a partition. It enables co-owners to divide the property or force its sale and split the proceeds.
Step-by-step explanation:
The action required to dissolve a tenants in common ownership if the owners cannot reach an agreement is called a partition. This legal process allows a co-owner of property to force the division of the property among the co-owners, so that each owner may have their separate portion or, if the property cannot be divided, to force the sale of the property and the distribution of the proceeds among the co-owners according to their respective interests.