According to the Solow model, what will be the long-term effect on world GDP per capita of a general increase in the general government budget deficit among the world's countries

a) GDP growth falls for 10-30 years, then returns to the original growth path.

b) GDP rises in the short term but is unaffected in the long term.

c) GDP per capita is not affected by the general government budget balance

d) GDP growth rises for 10-30 years and then returns to the original growth path.