参考答案：B

解析：

The amount of the spending program exactly offsets the amount of the tax increase, leaving the budget unaffected (balanced budget). The multiplier effect is stronger for government spending versus the tax increase. Therefore, the balanced budget multiplier will be positive. All of the government spending enters the economy as increased expenditure, whereas only a portion of the tax increase results in lessened expenditure (determined by the marginal propensity to consume) , because part of the tax increase will come from the savings of the taxpayer (determined by the marginal propensity to save).