make an objection
demur - object to something
When you ‘demur’, you do not agree with something or will not do something that you have been asked to do. It can also express hesitation caused by one's doubts, morals, or objections. The word connotes politeness and professionalism rather than a rude refusal or reluctance.
Some aspects about the way we conduct business is causing potential investors to demur.
To allow tempers to settle a little I requested a break in the meeting, but my manager demurred.
Jack accepted the new position without demur. He clearly had no doubts about it.