US STOCKS-Wall St rises, but oil continues to weigh
* Weakness in crude oil again pressures energy names
* Otsuka to buy Avanir; Cypress Semi to buy Spansion
* Biogen rallies on favorable Alzheimer's drug data
* Dow, S&P 500 both up 0.2 pct, Nasdaq up 0.3 pct (Updates to open)
By Ryan Vlastelica
NEW YORK, Dec 2 (Reuters) - U.S. stocks rose modestly on Tuesday as a pair of big M&A deals boosted market optimism and helped the market rebound from the broad decline in the previous session, which was the S&P 500's weakest day in a month.
Energy shares continued to struggle amid ongoing volatility in the price of oil. U.S. crude futures fell 2 percent to $67.58 per barrel, contributing to the 0.5 percent decline in the S&P Energy sector, the worst-performing industry group of 2014. Chesapeake Energy fell 1.3 percent to $19.80 while Devon Energy was off 1.3 percent at $59.14.
Crude is down more than 30 percent from a recent peak, and analysts expect the group's weakness to persist.
"Fourth-quarter earnings estimates for the energy sector are down about 20 percent, which is significant. There's going to be really broad pain when that materializes," said James Liu, global market strategist for JPMorgan Funds in Chicago. Continuación...