In the context of multi-factor theories and structural models of intelligence, which of the following statements is most appropriate and true regarding the interrelationship between the scientific nature of the three dimensions—'Operations', 'Contents', and 'Products'—under the 'Structure of Intellect (SOI) Model' proposed by J.P. Guilford, and 'Naturalistic Intelligence' and 'Existential Intelligence' under the 'Theory of Multiple Intelligences' proposed by Howard Gardner?

J.P. Guilford proposed the 'Structure of Intellect Model (SOI)', according to which intelligence is a three-dimensional matrix of three dimensions—Operations (5), Contents (5), and Products (6) (5 × 5 × 6 = 150, later increased to 180). On the other hand, Howard Gardner gave the 'Theory of Multiple Intelligences', which refutes the traditional 'g-factor' (single intelligence) and advocates independent intelligences (such as linguistic, logical-mathematical, spatial, musical, bodily-kinesthetic, interpersonal, intrapersonal, naturalistic, and existential intelligence). Here, statement (a) presents a completely correct and precise analysis of the scientific and conceptual nature of these two theories.