change MAY to can

openid-4-verifiable-presentations-1_0.md

@@ -577,7 +577,7 @@ When a VP Token is returned, the respective response MUST include the following
 `presentation_submission`:
 : REQUIRED. The `presentation_submission` element as defined in [@!DIF.PresentationExchange]. It contains mappings between the requested Verifiable Credentials and where to find them within the returned VP Token. This is expressed via elements in the `descriptor_map` array, known as Input Descriptor Mapping Objects. These objects contain a field called `path`, which, for this specification, MUST have the value `$` (top level root path) when only one Verifiable Presentation is contained in the VP Token, and MUST have the value `$[n]` (indexed path from root) when there are multiple Verifiable Presentations, where `n` is the index to select. The `path_nested` object inside an Input Descriptor Mapping Object is used to describe how to find a returned Credential within a Verifiable Presentation, and the value of the `path` field in it will ultimately depend on the credential format. Non-normative examples can be found further in this section. 
 
-Other parameters, such as `state` or `code` (from [@!RFC6749]), or `id_token` (from [@!OpenID.Core]), and `iss` (from [@RFC9207]) MAY be included in the response as defined in the respective specifications. `state` values MUST only contain ASCII URL safe characters (uppercase and lowercase letters, decimal digits, hyphen, period, underscore, and tilde). For the implementation considerations of a `state` parameter, see (#state_management).
+Other parameters, such as `state` or `code` (from [@!RFC6749]), or `id_token` (from [@!OpenID.Core]), and `iss` (from [@RFC9207]) can be included in the response as defined in the respective specifications. `state` values MUST only contain ASCII URL safe characters (uppercase and lowercase letters, decimal digits, hyphen, period, underscore, and tilde). For the implementation considerations of a `state` parameter, see (#state_management).
 
 The `presentation_submission` element MUST be included as a separate response parameter alongside the VP token. Clients MUST ignore any `presentation_submission` element included inside a Verifiable Presentation.