The correct answer is C, as the knowledge points clearly state that 'the Vermont Senate voted 26 to 4 last year against extending (its nuclear plant license's) period.' This indicates a negative reaction to Entergy's behavior, specifically opposing the extension of the nuclear plant's license. Options A, B, and D do not align with the information provided, as there is no mention of support, indifference, or praise from the Vermont Senate regarding Entergy's behavior.