Hi Alexander
@Archana Chandar is correct that you cannot filter attachments
However, you can do this by creating a view with the one attachment you want to send and use this view for a task and/or with an email node.

In testing this, my workflow

my initial view had two attachment controls.

Email node used view 1 so I receive this

2nd view removed one of the attachments - so I only have that one attached to the email.

Long story short, create a view with what you want for that task or email, and the attachments to the email received include just that.
Hope that helps!
Sigrid
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Sigrid Kok
*Precisely Software Inc.
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