WASHINGTON — The number of people seeking unemployment benefits rose last week after three weeks of decline. Even with the gain, applications remained at a level consistent with modest hiring. And the broader trend over the past month suggests job growth could pick up further in the new year. Weekly applications increased by 15,000 to a seasonally adjusted 381,000, the Labor Department said Thursday. The four-week average, a less volatile measure, dropped for the fourth straight week to 375,000.