Coherent Inc., Santa Clara, Calif., added the American Funds Growth Fund of America and Washington Mutual funds as investment options in its $100 million 401(k) plan, said Volk Scherle, director of benefits. The plan dropped an active domestic large-cap growth equity managed account run by Roger Engemann & Associates, Mr. Scherle said; he would not say why the firm was terminated. Officials considered other managed accounts in their shortlist search for new large-cap investment options, he said. The plan now offers 15 options, up from 14. Wells Fargo is trustee; Merrill Lynch is record keeper. Merrill Lynch Private Client Group assisted.