Which type of grant is made by an owner who is alive?

A grant made by an owner who is alive is accurately described as a private grant. This type of grant involves an individual or entity voluntarily transferring property rights to another party while both the grantor and grantee are living. Private grants can occur in various forms, such as a sale, gift, or other informal transaction, where the intent is clear and agreed upon between the parties involved.

Other types of grants mentioned, such as public grants, transfer by will, and involuntary grants, do not fit this scenario. Public grants typically involve government entities conveying property for public use or benefit, while a transfer by will involves the distribution of an estate after the grantor's death. An involuntary grant, on the other hand, refers to the transfer of property against the owner’s wishes, often due to legal action or statutory authority, which also does not apply here. Therefore, a private grant is the only option that accurately reflects a transaction involving an alive owner.