Which opera has more acts, Il matrimonio segreto or Lohengrin?
Lohengrin
Title: La cambiale di matrimonio
Passage: La cambiale di matrimonio (The Bill of Marriage or The Marriage Contract) is a one-act operatic farsa comica by Gioachino Rossini to a libretto by Gaetano Rossi.  The libretto was based on the play by Camillo Federici (1791) and a previous libretto by Giuseppe Checcherini for Carlo Coccia's 1807 opera, "Il matrimonio per lettera di cambio".  The opera debuted on 3 November 1810 at the Teatro San Moisè in Venice
Title: Lohengrin (opera)
Passage: Lohengrin, WWV 75, is a Romantic opera in three acts composed and written by Richard Wagner, first performed in 1850.  The story of the eponymous character is taken from medieval German romance, notably the "Parzival" of Wolfram von Eschenbach and its sequel, "Lohengrin", written by a different author, itself inspired by the epic of "Garin le Loherain".  It is part of the Knight of the Swan tradition.
Title: Il matrimonio segreto
Passage: Il matrimonio segreto ("The Secret Marriage") is an opera in two acts, music by Domenico Cimarosa, on a libretto by Giovanni Bertati, based on the play "The Clandestine Marriage" by George Colman the Elder and David Garrick.  It was first performed on 7 February 1792 at the Imperial Hofburg Theatre in Vienna in the presence of Emperor Leopold II.
Il matrimonio segreto Lohengrin (opera)