The Σ0 baryon, composed of the quark combination uds, is produced through the strong interaction between a π+ meson and a neutron. π+ + n →Σ0 + X What is the quark composition of X?

Multiple choice answers:A: u s-barB: u dC: u d-barD: u d s-barThis question requires you to have memorised:the quark content of a neutron and all the pions,that strangeness number and baryon number are conserved in strong interactions.
Compute strangeness and baryon number of LHS. From this we can deduce that of RHS. These numbers add, so we can write an algebraic equation for the two, knowing the properties of sigma-0 from the question. This allows us to see that A is the only viable answer.