Choose the best option:
1. The mechanism of electroweak symmetry breaking is one of the most important issues in the present Particle Physics.
2. They are required to give masses for all quarks and leptons and to guarantee the absence of the gauge anomaly.
3. In the standard electroweak model a fundamental Higgs doublet is introduced to cause the spontaneous symmetry breaking.
4. Supersymmetry (SUSY), eliminating all quadratic divergences, may provide a better theoretical basis to describe a fundamental Higgs boson with a relatively small mass to a high energy cutoff scale, say the Planck scale for example.

5. In the minimal SUSY extension of the standards electroweak model the Higgs sector consists of two chiral superfields of Higgs doublets (H1 and H2 with opposite hypercharges).